bluetooth: Return int8_t and use -128 for unknown tx power.

content/common/bluetooth/bluetooth_device.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/common/bluetooth/bluetooth_device.h"
 
 #include "base/strings/string_util.h"
 
 namespace content {
 
 BluetoothDevice::BluetoothDevice()
     : id(""),
       name(base::string16()),
-      tx_power(device::BluetoothDevice::kUnknownPower),
-      rssi(device::BluetoothDevice::kUnknownPower),
+      tx_power(device::BluetoothDevice::kUnknownTxPower),
+      rssi(device::BluetoothDevice::kUnknownRSSI),
       uuids() {}
 
 BluetoothDevice::BluetoothDevice(
     const std::string& id,
     const base::string16& name,
     int8_t tx_power,
     int8_t rssi,
     const std::vector<std::string>& uuids)
     : id(id),
       name(name),
       tx_power(tx_power),
       rssi(rssi),
       uuids(uuids) {}
 
 BluetoothDevice::~BluetoothDevice() {
 }
 
 // static
 std::vector<std::string> BluetoothDevice::UUIDsFromBluetoothUUIDs(
     const device::BluetoothDevice::UUIDList& uuid_list) {
   std::vector<std::string> uuids;
   uuids.reserve(uuid_list.size());
   for (const auto& it : uuid_list)
     uuids.push_back(it.canonical_value());
   return uuids;
 }
 
-// static
-int8_t BluetoothDevice::ValidatePower(int16_t power) {
-  return ((power < -127) || (power > 127)) ? BluetoothDevice::kUnknownPower
-                                           : power;
-}
-
 }  // namespace content